Hmm, I get your point, upvoting -- but I'm not sure that "2+2=4" is meaningful in the same sense that "Bob already had 2 apples and bought 2 more apples, he was now in possession of 4 apples" is meaningful.

To the extent that 2+2=4 is just a matter of extending mathematical definitions from Peano Arithmetic, it's as meaningful as saying 1=1 -- less a matter of beliefs, and more of a matter of definitions. And as far as it represents real events occurring, we can indeed imagine surreal fictional universes where if you buy two apples when you have already two apples, you end up in possession of five or six or zero apples...